I have a 65 Chevelle Malibu SS, it has a 454 in it, I know that 454 did not come in chevelles in 65 but what I was wondering if someone could tell me what engine it is.Ls4 Ls5 or what. It has been built, has lots of power, but I dont much other then that. the numbers I got off of the back of the engine near the fly wheel are, any help would be greatly appriciated.

it looks like ( L 4 and it looks like 78, it could be 73)
GM T12
3999289 Engine numbers

and the heads numbers are
GM 12T
P
A22-77
336781 PassX

For casting numbers here is a link that you will want to save http://www.mortec.com/

Bill

Thanks for the reply, but all it tells me is what I already know, that it is a 454, but it does not say if it is a LS4 or LS5 or anything of that matter and thats really what id like to know if anyone can help me. thanks again